When I was in training as a Marine, I remember one particularly grueling exercise where we were deposited in the center of Dartmoor, England. We were told to make our way on foot to a certain point on the map more than fifty rugged miles away. As we had done a similar journey the previous day, slept out on hard ground for a number of nights, and been brought slowly to the point of physical and mental exhaustion, we knew that it was going to be a long day. What we didn’t know was that my partner’s feet, which had a tendency to blister, would become so badly worn after a few miles that they would become like pieces of raw meat. When I realized he was in pain, I took his equipment and added it to mine. Later I supported him on my shoulder as he hobbled along, but it became increasingly plain to me and to the colleagues who caught up with us that he wasn’t going to make it. But he was made of stern stuff and he insisted that he would keep going, that we should go on and stop worrying about him. After many more excruciating miles, however, he came to the point of admitting he was through, and then I was able to pick him up, put him across my
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